EMI shields are useful for many purposes, specifically for protecting forensic evidence. If a portable wireless device is taken from its owner it is important to ensure that the data on the device is not altered in any way from the point of seizure. One method of ensuring this is to shield the device from incoming or outgoing wireless signals using a portable EMI enclosure. It is often desirable to access the device inside of the EMI enclosure to forensically analyze the data it contains while keeping the evidence shielded from EMI signals. It may also be desirable to charge the device while inside of the EMI enclosure.
Prior to this invention, portable EMI enclosures did not provide a method for maintaining EMI shielding while accessing the device inside via cable for either data acquisition, charging, or both. Thus, there is a need for a method of accessing and connecting to a portable wireless device via cable while it is inside of a portable EMI enclosure, without compromising the shielding.
It is also desirable, or sometimes necessary, to manually operate a device inside of a portable EMI enclosure. Portable wireless devices with touchscreens are particularly problematic to operate inside of portable EMI enclosures. Thus, there is also a need for a method of operating portable wireless devices with touchscreens inside of portable EMI enclosures.
Portable EMI shields that allow one to preview devices contained therein shield EMI signals less effectively than portable EMI enclosures that do not allow one to preview the devices contained inside. This is most often noticed when transporting wireless devices inside of EMI enclosures. The reason why this is most often noticed during transport is because it is at this time that a portable wireless device could come close to a signal tower. The closer a wireless device is to a signal tower, the better chance it will have of connecting with the signal from that tower, rendering the EMI enclosure useless.
EMI enclosures that allow access to a device within the enclosure and shield signals effectively exist but they are not portable. They are heavy, metal-lined enclosures as in U.S. Pat. No. 5,594,200 to Ramsey.
Many prior art portable EMI enclosures do not allow cable access to a device inside without compromising their shielding. When operated correctly, they are bags that become a sealed container as in U.S. Pat. No. 7,601,921 to Shroader.
Also, prior art portable EMI enclosures do not allow a human to operate a touchscreen device inside, and prior art portable EMI enclosures that allow a preview of devices inside shield less effectively than portable EMI enclosures that do not allow preview.